The objectives of this proposal are to determine the optimal model for the study of arthroplasty tissue regenerated from transplanted rib perichondrium, and then to characterize the repair surface. This characterization will include biochemical, biomechanical, and morphological techniques including autoradiographic studies. The significant rate of failure of total joint replacement surgery has stimulated a renewed interest in biological arthroplasty, particularly for young or middle aged patients. The recent observation that rib perichondrium transplanted to a joint will proliferate to form hyaline cartilage offers an exciting avenue for a new research direction in this field.